The plummeting price of renewable energy has bankrupted more than two dozen wind and solar manufacturers, but the BNEF analysts say it could lead to a tripling of investment in the sector over the next 17 years. Notable victims of the falling costs of solar panels include Solyndra and Suntech. But the collapse of those companies appears to be little more than natural attrition in a fast-evolving industry with an extremely bright future.

Annual spending on clean-energy projects that don’t add to greenhouse-gas pollution may rise to $630 billion at the end of the next decade from $190 billion last year, Bloomberg New Energy Finance said in a report today. That’s 37 percent more than estimated in November 2011 and means renewables would account for half of all generation capacity by 2030. …

While suppliers are suffering, lower equipment prices are making more projects profitable to develop and advancing the day when renewables can rival coal and oil on cost.

“The apocalyptic views about what it will cost to shift the world to renewable energy simply aren’t true,” Michael Liebreich, chief executive officer of New Energy Finance, said in an interview. “Three years ago, we thought wind and solar would be cheap as chips, and they’ve even gone below that.”

Despite noise made on the right, the failures of high-profile renewable energy companies don’t mean that the sector is failing. Quite the opposite.